As external electrodes in a conventional multi-layer piezoelectric element, as disclosed in Patent Literature 1, there are used external electrodes made of conductive paste including a conductive material such as silver, and glass, and adhered to side faces of a stacked body. This conductive paste is applied to the side faces of the stacked body, and is baked to form external electrodes.
In the multi-layer piezoelectric element, it is required to secure a large amount of displacement under a high pressure simultaneously with progress of miniaturization. Therefore, it is required that a higher electric field is applied to the multi-layer piezoelectric element, and the multi-layer piezoelectric element can be used under severe conditions of being continuously driven for a prolonged period of time.